Switch throwing and locking mechanism



C. C. THORN SWITCH THROWING AND LOCKING MECHANISM 5 Sheets-Sheet l Filed April 8. 192.6

De.z7,1927. 1,654,023

C. C. THORN SWITCH THRowING AND LOCKING MEcHANxsM Filed April a. 192e 5 sheets-sheet 2 C. C. THORN SWITCH THROWING AND LOCKING MEGHANISM Dec. 27, 1927.

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Dec. 27, 1927. 1,654,023

c. c. THORN SWIICH vTHRowING AND LOCKING MECHANISM Filed April 8. 1926 5 Sheets-Sheet .4

wwf i Dec. 27, 1927. 1,654,023

c. c. 'rHoRN SWITCH THROWING AND LOCKING MCHANISM Filed April 8. `1926 5 SheetswSheat 45 uri ffii

Patente Dec. 27, 1927.

PATENT OFFICE..

CHARLES C. THORN. 0F GAMI'JEN, JERSEY.

SWTCH TIIRO'WNG- AND LOCKING MECHANISM.

Application flied April S, 1926.

i1 cpcratine; li

Etty invention rr-ietce te envite and l tontrci incciianieni for railway track use, beet suited te crosse-overs a ui tlnneute. Une purper-:e et my invention to eeni jpiity operation and to improve tile nretecI tioi'i given againstiucoiieietcnt operation et separate avvii' .ties anzi/or switcher.' and (ierails.

tile

ien

'between a 11min track anti a :'siiiinga; L t ic iofiiticn et the siding .en/itch and a tiere i l uur device or einer awitcii iiicr--reia'cit with the tiret inviten.

It further purpose is to :uiniitionaily ne tcct :inviten inecinniien; cmui'oiicfi by a. center iecking' lever.

ik iiurtiier purpose 'la to remove the nimmt ingr eiifect of passing' trani :troni (ne encino ingr mechanism ot a. -;v.'itcii and. take it. un init i, bofi'v of the Switch, at Nie a ine. time avoicmiig rink et' tiae pounding revel-engr tin: punition et' the throwing; lever. l

ik :further purpose to litt the oneratiunj ineci'aanifnn eut et thc water and dirt ci (ne track.

.it tui-ther purpose is to operate a :lfwitcii in' a {rear-operated piatte cani ttireucii a crank with .vi ich the ain ci'lga'ree.

it. further purpese of this: de nro-y vieu at the switch invwivea nieane ot' operating; and pcriniasibtv locking;l the switch by the use ot one kami lever, andtc inctinie therein cinitacte ee that. a track circuit it ueci'i witi eiinnter: betere thc 1:-v.'itc`. unlocked. insuring that all signals; invotvcil iviii be returned to their moet rc 1trii-ti`^uc iniiicetiini.

F n'tiier purposes xviii anpe; in tiie encriti ,a iene and in 'the claims.

t Pretec to illustrate inv inva1 #single itorin oniy among 'the 'ariete` torina iu which .it may appear, eeiergftingg one which ie practi al, c'ti'ective and reliable and, which at the saine tinlc weil iiiuetratcss the `prin cipiee involved.

Figure 1 is ton `pian vien' oi a switchoperatingI mechanism and circuit cfnirotier cn'iboii'ving my invcnticn'i, the top it" the cir Serial N0, 100,473.

cuit controller being;l removed tor clearncee.

Figure. 2 is a. .eide eievation ot the etructure eeen in l `i, ure l with the top in piace. Figures it", l", t and 2, E5@ cc 1f`reeprnnt in part with ft and 2, respectively but are fragmentary, on rcrili efl|V ecaic and Show inediticaticns; ott the parte.

Figure 3 ie an cniarggcr'i "traenientarv section oii' Figure '1 taken upon tlic line ifi-5%.

fig'urc It ie a :tifagnnciltary section. of Figure l upon tine i et. J

iigg'aree 5i, and are it'ranlneilaijv ton plan vieiva oL tracks; and ewitchee to which my invention muy be applied..

In the ci 'awingre Hiniiiar ninneri'iie indicate like i i.

Vi the arrangenieilt at present generally in nee on ay turnout from Inain rtrack tc Hiding when the twitch hai; in reve 'eed and the derail has been taken @if the track, 'Y Switch. can be put back to normal and tile. the train ain ,en awajjf Atcavinn` the derail 'for the airline; ott the tinck. This maken it noeaible tor a. car or care on the siding,r te (tritt en to the main track, which ironici be particularly danni-irene it track circuits were not uned. it ie neceeeary with the existent arranrement tor the train man to manipulate 'hie switch key twice to unlock the levers. '.iticee objections ha ve been corrected bv me by throwing the derail from tile Switch and, cmi-eenendingiv, one icck only is required. In the c; :fie of a crees over between a main track and a siding, with the arrangement at preeent ,C gei'ieraiiy in use the Switch in the main t ack may be put to norinai after .in-.finigi; been reversed and the train may then leave 'without putt' "i 'the A "ne: switch in its noru'iai position rnd niri mit throwing the locking; lever te teck both ew'itcl'ics. This; leaves the main track :Witch unlocked and would allow a car to dritt out from the Siding to the inain track. This objectionyiiae been overcome by lne by requiring the contact-nient of the .finding switch te neil-inni, aiter it naa been thrown, betere the main tinck Switch can be replaced to normal and by insuringthat the signals involved shalt return to their mest reatrictive indications.

In the case ot a cross over between inain tracks, the device at present in general use requires a facingpoint lock and circuit c0ntroller at each end of the crossover and a Switch throivil'ie; device, which are combined in a Single device in the new mechanism.

My switch throwing mechanism is shown in Figures 1 and 2 as mounted within a casing 9, .adapted to be held in place by apertured lugs 10. It is protected by cover members 11 and 12 and a gear casing 13,

which may be combined with one of the cover members. y

vThe interior of the easing receives and guides a. sliding plate 14 having-gear teeth 15 upon its upper surface and a cam slot 16 within its lower surface. The cam slot comprises terminal straight locking portions 17 and 18 and an intermediate diagonal operating `portion 19 bounded by cam surfaces 20 and 21. The straight portions 17 and 18 are bounded by parallel edges 22, 23, 24 and 25.l

The sliding plate 14, referred to herein also asa cam plate because it carries the cam, is connected in any suitable way as by rivets 26 with a lbar 27 apertured at 28. which bar isconnected in different forms of my invention with switches or other apparatusjwhich are `to be thrown by this operating mechanism or whichexcerise a conv29 provided with caps 30, forming bearings for a shaft 31 upon which are rigidly mounted a segmental gear 32 engaging with rack 15and a switch lever33 by which the gear .is turned to throw the rack to the right or to the left of its normal position.

Within the cam slot 16 I place a pin 34 mounted upon a c-rank carried by shaft 36. Y Upon theouter end of this shaft is keyed switch operating arm 37 apertured at 38 and adapted to be connected in any ksuitable way with the switch to be thrown.

In operation, as so fardescribed, the members are shown in the drawings in the normal position in which the switch is locked and in which the switch throwing lever 33 is infact locked. The switch connections are made through arm 37. Y

When the operating lever 33 is thrown upwardly and to the left from the position shown in igure 2 the segmental gear engages the rack carrying it to the right. This first causes the straightv portion 18 of the cam slot to pass lengthwise of the pin 341 and subsequently causes the cam surface 2O to bear upon the pin and force the pin toward' the bottom` of the sheet in Figure 1 until it is in line with the straight part 17 of. the'cam slot. vThe fact that the portions 17 and 18 are straight causes continued movement of the cam plate to lock the pin 34 without'further turning of the pin after it has been thrown by either vcam surface, and continued movement of the cam plate therefore locks the pin withiny the straight portion 17. The bar 27 has meantime been moved to the right in the figures.

Reversal of throw of switch-throwing arm 33 unlocks the pin, throws it in clockwise direction by means of cam surface 21 and locks it again within the portion 18 of the slot, meantime turning switch lever 35 in clockwise direction (Figure 1) and moving bar 27 to the left as seen in Figures 1 and 2.

The straight sides of the portions 17 and 18, substantially perpendicular to the direction of rotation of pin 34 where it engages them, relieve the cam plate from strain in a direction parallel to its direction et movement and avoid any tendency to reverse the lever in the two posit-ions in which it is intended to be thrown. fers any reversing pressure to the casing.

The cover 11 may merely complete the cover of the casing or frame when no electrical control is intended or, as shown in the illustration it may form the means of mounting an electrical control shown at the left in Figures 1 and 2 and shown in more full detail in Figures 3 and 4. ln this latter case the rack bar carries a slide 3f) shown as riveted to it.

The slide 39 is adapted to pass through notches in the facing point witch bars 40 and 41 so as to lock them in the position shown in Figures 1 and 2 but to release these lock bars when the lever 1.2 is swung to the left in these figures.

Wlhere no electrical control is to be used the structure terminates at this point. For electrical control a cam dog 42 is secured to the slide bar 39 as by riveting at 43. This cam dog controls the position of a rocking lever 44 pivoted at so as to roel; the lever about the pivot- One cam 'tace 46 engages the corresponding face 47 of the rocking lever to tilt the lever in clockwise direction (Figure 3) into the position seen in this figure wnen the switch throwing lever is being thrown in clokwise direction as measured in Figure 2. The other cam face 48 engages with a cooperating fare 49 upon the lever to swing it. in counterclockwise direction with reverse, tha counter clockwise swinging movement (Figure 2) of lever 83.

The pivot receives lwaxinfr support in a special cover 50 used when electrical connections are to be made by this switch. The cover is extended to provide a bex 51. within which are lead conductors 55, 5G suitable interior connecting wires and the contacts 57, 58. l\lormal contacts 57 of any suitable number are connected together into two groups as by plates 5f) and (i0 but require no insulation their multiplicity is for the purpose only of insuring god contact. Likewise the contacts 58, though insulated from contacts 57 and from cach other by a block ordinarily require no insulation as the complete return from the contacts 57 is made through them. Ad-

n ci no lt thus trans- I' lll) llit) ditional openings (i2 appear' in the hottoin ot' the hoi: for any extra contacts that are "y or perinit.

tlonnected with the cover 50 in any enit alix-le way ie a plate (i3 carrying a guide Gil ior poet G5. The poet lterni?aatee in a traine GG hy which the Contact lingers 5"? are lifted and lowered iso as to disengage troni or en- With contact lingers 58. The post ($5 is connected in i Suitable nuinner at 67n here hy a pivot7 with one end oi the roching; lever il with the result and elifect that clockwise rocking inovenient oil the lever Lle-t litte the poet and sep; intact fingere iii" troni contactling'e. is 58, Where an counter clocliwiifie tilting` .inox/'ement ol. thin lever loivere the poet G5 and lowers the contact lingen; into engagement with contact lii'injers 5&3.

The cover GE ie hinged at (39 so ae te inalre the parte Iquite accessible when the cover ia opened and is latehed hy a catch TO swung 'ti-nin strain; 'il and ei'igag'ini over hook 'it :lorniingl a catch euch as ie used generally on r'eiianratore. The latch slips over a haep eve i3 permitting; locking` o the parte.

Figi-ure l ie intended to `he identical with llig'ure 'l in the portion shown except as har 2T is cut or interrupted at 74. so that the inner end 12?" can shove the outer end 272 to the right oii the ligure or can prevent replacementet the outer end it the latter has heen nioved to the right. There a niain track :switch and Siding switch are to he need tor a croce overj 'lor exaniple, an individual har ot the inain track switch throwing mechanism may he connected to the eut end oi? the Siding* switch throwing niechaniein :so that the siding; Switch can not he thrown `until the main track switch hat,` heen thrown to nieve thin portion. Q72 ont oli the way.'L lllilcewiee A,i'hen the @filing` eivitch has heen thrown the inain track sia'iich can not he replaced until the Siding; fnvitch hanl heen returned to position.

'taking' up the apolication oit nay inventien to derail cnntrole at Sittings and at 'nrierfrrcie` lf show the :invention applied to rol ol" a derail in Figure 5 where the inain tract; ist Shown above, the eiding;l he lon'7 and the tivo ends oit' the connection are shown complete with a Short intermediate Section, Showing' those portione o'l the track at which the hell cranks are placed for change ot direction oi pall and thruet ot the operating; pipe connections.

The switch pointe 75 are 'connected ae ueual hv liront and lock .rod 7G operating;l Signal light 'Z7 and lock hars 40, 4l.. The awitch throwingI inechaniein shown in I. 'fijures l and 2 may he used with or Without the :attachment 'for electrical connections, operating; rnd 'itl being throvi'n hy Switch operating;

crank 37. In this` Figure 5 the switch throwing lever 33 has heen placed on the oppoeite end of the pin 3l troni its position in Figures l and 2.

With the` parte in the position ehown, an

undercut :tor 27 et my Switch throwing` 1nechaniei'n .iS connected with derail point 7S) hv pipingr 8l), 8l. and 82, hell cranks Sii, Sit, 85 and operating rod coniiectione` 8G. The derail is set inv Figure 5 lor dei-ailing. When the Switch throwing' lever is thrown to the .left o'l Figure 5 the ewitch ie operated to connect the inain tract; with the siding;` and the derail thrown oil,` that ie :iet to perinit this connection. TWith replacement ot the switch throwing lever the switch in the inain track will he thrown into the poeitiiin shown and the derail will airain he eet ior derailingif. The result would he the naine whatever the type et' derail need hut the cliaracter olf movement would. have to correspond with the derail need.

ln Figure (5 are Shown a main tinckY helow and a siding ahove, lor which two twitch ojierating inechaiiisine are used to control a croeilfoifer. In these the operating; alcoli an sin at the right controle the inain switch and is correepondingly placed as chown. .la the switch at the upper left, controlling; the eidingij, the har Sli" is cut ae in .Figure l to that7 as explained abovej the thrtm'iin;` ot the inain switch, inust take place to nieve the outer end 272 of its har heiore the siding;l switch can he thrown to open the track to the Siding, and, correspondingly, the siding;A switch n'iuet he replaced hetero the niain tracli; switch can lie replaced. The piping; connections SO, Sl, 82 and hell cranks; Si?, i 1l 8a have been traced from the inain switch, operating niechaniern in this: caen, corre nprinding to their tracing 'l'roin the only savitch inperating mechanism in Figure ln the crossover shown in Figure 'i' ihn end omitted at the left is a duijilicatii'in oi' that shoiitn except that the illustration uou hl he turned through an :mele ou liti degree l-lere the rulee oit the hei railroafli:require a little ditlerent arraingjeinent oi the partel in view ol the tact that two inain tracht: arc involved and that in operation there inuethe protection troni throwing ot the ,livin-hea while a car ie on the ,croiisoveix I therefore show the required loclehar locking; lever 87, throwingl rode S9, titi', 85)" and hell cranks 90. liv `which the locking; impulse i'or the tivo awitchee eli'ecied and the signale are cleared. Thin operating): part is old in the art hut the application to or rather through niv mechanism is; new.

The switch operatingn mechanisms at the two switches are intended to he alilie and need per'liorin no other function here than 'thc actual throwing of the ewitch. However: they are clesirahly Ialtered as in Figures Ilb and 2l to perinit the saine lockingl mechanical l lill and circuit controller to be used as in the other forms. No change is required except to substitute a new bar 39 for the bars 27 and 39, passing it through the mechanism over the rack and free from attachment to the rack.

In the switchy throwing mechanism 9 used in each of theseswitches and shown in Figures lb and 2b, the motion plate carrying the rack and cam is unchanged but the rod S9 connects with a bar 39 which passes through above the rack. rlhe segmental gear 32 is displaced laterally to permit this bar 39 to pass to one side of this gear. The bar 39 is also cut at the edge at 9i `to allow more room and isadditionallyv recessed at 92, providing a step at 93 for the purpose of interlocking the locking lever 87 and `its connections with the two switch throwing mechanisms.

This interlocking is secured by passing a stop lug 94 upon the side ot' the segmental gear in such position that when the locking lever 87 is thrown to pass the bar 39k into the apertures in lock rods LlO and all the stop lug 94 will lie over the step 93 preventing` movement of the switchy throwing lever 33 and eifectually protecting against the switch throwing mechanism bringing any strain upon the switch. The stop lug etl'ective to block movement of rthe lever much beforethe lever'would cause movement ot the motion plate to clear the pin 3ft of the straight part of the slot and therefore blocks turning movement of the switch throwing lever before the cam surface of the motion plate engages this pin 34.

It will be obvious that the direction of movement of the switch throwing lever may be reversed by mere reversal of the direction of the cam groove in the cam pla-te, that the 27, cut or uncut extensions or/and that the switch throwing lever may be placed upon either end of the shaft 3l, all as indicated in Figure lc and 2C, providing for a great variety in the relations ot' the. movements secured to suit the needs of any7 location that may be desired beside the track and to provide any y interconnection (i1-interlocking ol the parts (itl with other switch which may be sought.

' In View of my invention and disclosure variations and moditications to meet individual whim or particular need will doubtless become evident to others skilled in the art., to obtain part or all of the beneiitsvoi my invention without copying the structure shown, and I, therefore, claim all such in so far as they tall within the reasonable spirit and scope of my invention.

Having thus describedmy invention, what I claim as new and desire to secure by Letters Patent is i operating mechanism an operating lever, a gear rotated thereby, a

nersfaoea rack engaged by the gear and carrying an eccentric thereinhaving operating faces etfective with movement in opposite directions and holding faces etliective at the end ot each movement, a rocker shaft having a portion cooperating with the cam by which it is thrown and held in posit-ion as thrown and a crank on said rocker shaft adapted ttor connection to throw a switch.

ln an operating mechanism for switches, an operating lever, a gear rotated thereby, a rack engaged by the gear and carrying a cam therein having operating Ylaces ellectivc with movement in opposite directions and holding 'faces cllcctive at the end olf cach movement, a rocker sl ai't having a portion cooperating with the cam by which it is thrown and held in position as thrown and a crank on said rocker sha'lt adapted vtor connection to throw a switch, said crank operating in ay plane perpendicular to the plane ot operation ot the switch throwing lever.

3. In switch throwing mechanism, a pivoted switch throwing lever movable in a vertical plane parallel to the track. a gear operated by the lever, a rack moved by the gear, a cam carried by the rack` a switch-operating crank moved by the cam toward and from the track and an operating bar carried by the rack plate and movable along the track divided in two parts each Apart operating as a check upon or movable by the other part.

4l. In .switch throwing mechanism a pivoted switch throwingl lever movable in a vert-ical plane parallel to the track. a gear operated by the lever, a rack moved by the gear, a cam carried by the rack, a switch operating crank moved by the cam toward and from the track and an operating bar carried by one end of the rack movable along the track and switch-locking mechanism at the opposite end ot the rack.

5. In switch throwing mechanif-em, a pivoted switch throwing lever movable in a vcriical plane parallel to the track. a g *ar opcrated hy the lever, a rack moved by thc gear. a cam carried by tho rack, a switch-operating crank moved by the cam toward and trom the track and an operating bar carried by one end of the rack and movable along the track, locking mechanism at the o|,)posi te end ot' the rack, a com carried by the lock mechanism, a rocking leve` swung by said cam and connections whereby electric contacts are made and opened with rocking movement of the rocking lever.

6. In switch throwing meclmnism, a trame, a rack plate guided within the frame, a gear connected to engage the rack, and throw it, a shaft for the gear, a switchthrowingl lever upon the shatt, cam surfaces and locking surfaces carried by the rack, a lever arm cooperating with the cam to he thrown by it and held in position at both lli Llo

ende ot the throw, n Stn-ift tor the Alever erin, zi sWitch-operntin,fr crank Aupon the ehnalt movable in e horizontal plaine tcnvzird and from the track, connectione troni the crunk te throw the enfilcli. lock rode inovxible with the switch and n, lock bnr carried by the roel; plete engaging with the lock rode.

7. In Switch throWin53,l mechanism :i Home,

n ruck guided Within the lrnino, n @our con- `nected'lo lr-nggjng'c the rock lend throw it, n elnilit ttor `the geni', :i Switch-l'brewing lever upon the erhalt, 'oni elntncee :ind flockiin; surfaces carried by the rnc/ln n. lover erin cooperating with `the coni to be thrown by it and held in position :it both ende ot the throwim e, ehn'lft tor the zirn'i, o onfitch-opernting crank upon the ehet't movable toward und trono the track, connections 'troni the crank to throw the switch, lock rode movable with the switch a` lock carried by the rack engaging with the lock rods and e Second switch member operated by the pull end thrust olf the rack.

8. A switch throwing lever, :1. plete operated thereby, switch throwingl connections .troni said plete, ay can), operated by the plat-e1 n rocking lever pivoted nein' the cznn having; coin engaging devices :it oppoeite slides olf its pivot point, guided conteet-nniking and breaking devicee and connectioiie between seid devicesI :ind one end ot the lever,

whereby,7 operation ot the coin tilte the lever i and lifts or lowers; the contnct-nniking devices.

9. ,ln e switch throwing` mechanism, n switch throwing' lever, n geni' retarded thereby, n rock engeged by the gear, n` com inovoble with the rack 'find having interinon diete operating :feces :ind end holding faces, :i rocker shaft having :in erin engaged by Seid coin and e second arm adopted to throw e switch und ai.v lockingl connection Wit-h Seid rock adapted to engage the lock rode ol the switch. :it one end oit its stroke :1nd be relosteed ii'roin llieni :it interniedizite tinten, :ind :it the other end oit Seid stroke.

l0. ln o turn ont :troni e. ninin triick lo n o' g, e mein track ewitcln o evvitch nhl-mvrnp; lever, a plate reeiproceted ther1 bro o.

dereil, thrust eonnectione troni the plete lo the dereih :i cern carried by seid plete, :i inviten throwing; crnnf connected with the elvltcl'n opereled by the coni sind held. in locked position et the extremities oit the cnnl movement, zi .lock rod oonnecliecfl with the enfil'eh und locking' mechanism carried by the plete end adapted to engage the lock rod.

ll. ln a. turn ont troni a inztin truck to n siding, a. moin track switch, :i switch-throwing lever, e, plate reciprocoted thereby, a derail thrust end pull conneetione1 :troni the plete to the derail, nl com carried by Seid plete, n switch-throwing crank conifiected with the switch and operated by the com7 e lock rod connected with the switch. :1nd looteintar mechanism carried by the plete end engaging the lock rod.

.12. ln :i Groe-(wertroni :l nnlin lai-:ick to n. Siding, :i rnnin truck switch, :i siding; Switch1 :i nniin l'rlck switch `ojjierntingr nioelniniz-ina comprising n. switch-throwing.; lever. n plete roeiprocziterl thereby, :l com cnrried by 'the philo,- n :ovitcliopernlino; crnnk erin niovcll hv enit! canin onlinr-.tiene to llnx s-switch, lockingr nleclninifon 'lor the switch carried b v the pietro :i willing); .envitch coinprieiing;l ai switchlhrowing lever, :i pleito ieclyn'ocnted llierelglv, :i anni carried by the pleite, n twitch throw ingr crank erin operated by the coni, connections to the envitch, and `a. lock for the ewitch carried by the plete, connections between the lnvitchee coinprieinpy boro in line ot' recipro cation both connected with the plete and one cnt to Ytree the outer part troni the port operated by the plete end connectione between the oiiter ende ot the two bere whereby the throwing ot the sliding ewiteh trom normal ie prevented. until the throwing ot the main switch hee moved the outer part ol.l the eid i ing,l switch bnr, end the throwing` of the oidil ing switch cliueee the inner end ot the bin.' upon the siding Switch plate to interfere with movement ot the innin truck switch. to norninl by interference with the nioveinei'it ol'v the outer part ot the bnr nntll the eide tree-lt Switch ie replaced to normal.

13. ln :i cross-over trein e nniiin tinck to n siding, :i mein trfick eivitch comprifisinn vitch throwing and locking ineclinniein :ind :L ber recprocnted by inoveinente o'l the inechniein, e moin track. switch thrown theren by, al side track switch, o Side Switch throwing and locking inecl'inniein havinie1 n. bnr moved thereby and coni'iections from the bar ot the Innin track switch into the path olf inovelll' nient of the bnr of the side track switch pre venting movement ot the eide tinck switch from nornnil until. the I'nztin track Switch line been thrown ilfroin norn'nil und, when the eide track Switch line been thrown. troni. nornnil, pi'oveiitingi` repleceiiiiient. oit the moin ti-nek @Witch to norinnl until the side track @Witch time been replaced lll. In o Groen-own: Atroni. ai moin tinck, the combination ot mein track find snvitcliee, nniin track end Sliding: throwing :ind lockingnieclieninnie ond connections between the n'niin track evvitcl'l sind siding ewitch interfering with niovenient ol the siding eivitch throwing; nieclnrnieni when 'the nniin truck switch le 'in normal p eitioin und interfering with replacement oit the nniin track switch to i'lorinnl when the eide track switch. is in. other than normal position.

l5, In n crose-over between tivo moin trucks, the combination ot' two mein track switches, tivo main track switch 'lilirowvinl inechenienn's, inter]netting between two nl track throwmechanisme requiring throvinol ol? one to nornnil et i it line been thrown 'lll l il) VYfor the cross-over before the other can be thrown Vto normal and common locking` mechanism for both Ina-in track switches.

16. In a cross-over .between two main tracks, main track switches in the two main tracks and switch operating mechanisms for the two s Yitches comprising` a throwing lever anclconnections from the throwing lever to the switch point to throw the switches, common locking mechanism for the two switches and interlocking between the locking mechanism and each of the throwinglevers.

17. In a. cross-over between two main tracks, main track switches in the two main tracks, apertured locking rods from the two switches, common locking mechanism for each ot the switches terminating in bars entering the locking rods, switch operating mechanisms, one for each switch, comprising pivoted switch throwing levers and connections from the switch throwing levers to thc switches and interlocking connections bctwcen the locking bars and the switch throwing levers preventing,r movement ot thc switch throwing levers until the locking bars are withdrawn.

CHARLES C. 'IVHURNQ 

